The present invention generally relates to a controlling apparatus for a laser diode which is used in a laser printer or the like to transmit laser beam light rays.
Generally the output characteristics of the laser diode are shown in FIG. 2. Conventionally, the current from 0 to In has been divided into many stages to control the radiation output. Such output control as described hereinabove has been performed by a circuit or the like.
In the output control of the conventional laser diode, the control object period is from 0 to In of the output characteristics of the laser diode, so that the high-precision controlling operation cannot be performed by the circuit or the like, and a complicated circuit is required to perform this high-precision control.